The Covid-19 vaccine developed by BioNTech and Pfizer has been shown to work against one of the most concerning mutations in the highly transmissible variants of coronavirus discovered in the UK and South Africa, according to a laboratory study.
Researchers at Pfizer and the University of Texas found that the vaccine can neutralise a virus engineered to contain the N501Y mutation, which had worried scientists because it is in a key position on the spike protein the virus uses to enter a cell.
Scientists tested the engineered virus against antibodies from 20 trial participants who had been vaccinated. The antibodies were able to neutralise the virus just as effectively as when targeting the previous coronavirus variant.
Scientists said the discovery was an important step towards guaranteeing the efficacy of the vaccine against the new variants. However, they cautioned that the study — which has been published online but not yet peer-reviewed — was not proof that the vaccine works against all of the mutations in the UK and South African variants.
Importantly, the vaccine has not yet been tested against another mutation on the spike protein in the South African variant, which a group of scientists warned earlier this week could make some vaccines less effective.
Pei-Yong Shi, a professor of molecular biology at the University of Texas, told the Financial Times that the result was “great news”, adding that testing of the vaccine against the other mutations would continue.
“We should monitor the type of new changes in virus and make sure they remain to be potently inhibited by the vaccine or therapeutic antibodies,” he said. “But if those studies indicate the vaccine is losing its activity against the new strain, then it is ultimately, immediately important to consider switching the sequence.”
Instead of using a virus that was discovered “in the wild”, the scientists genetically engineered the key mutation. Mr Shi said this approach allowed them to isolate those mutations that were most important. The laboratory has not yet obtained samples of the actual UK variant, but expects to receive some next week, he said.
Vaccine makers are eager to test their shots against the new variants as quickly as possible. Mr Shi added that he expected “very similar” results for the Moderna vaccine.
The BioNTech/Pfizer and Moderna vaccines are both based on messengerRNA technology, which could be adapted to cope with new coronavirus variants more quickly than other vaccine platforms by plugging in the new genetic code.
Independent experts gave the study a cautious welcome. “This is good news, mainly because it is not bad news,” said Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine.
“Had the opposite result been found, that the vaccine did not seem to have efficacy against the variation of the virus studied, that would have been bad and very concerning,” he added.
Eleanor Riley, professor of immunology at the University of Edinburgh, said: “So far, so good. There will be other new mutants and we will need to monitor the situation carefully by repeating this type of study on new variants as they appear. It may be necessary to tweak the vaccine over time.”